IMD predicts 106% rainfall of long period average during June-September monsoon season

The India Meteorological Department (IMD) forecast “above normal” rain during the June-September monsoon, boosting the prospects of a bountiful agricultural harvest that will likely ease inflationary pressure and bolster growth.

This comes as a relief after uneven rain in 2023, mainly due to the El Nino effect, leading to patchy farm output that pushed up food prices and kept the central bank from cutting interest rates.

The southwest monsoon is expected to make onset over Kerala around May 31 against the normal date of June 1 and “its advance soi far has been near normal and conditions will continue to be favourable for its onset over Indian mainland,” said Mrutyunjay Mohapatra, director general of meteorology, IMD.

Rain in the country during the four month long monsoon season is expected to be 106% of the long period average (LPA) with a 4% margin of error, according to the weather office’s second forecast. The first forecast also predicted 106% rainfall for the season.

The IMD defines average or normal rainfall as ranging between 96% and 104% of a 50-year average of 87 cm for the season.

The southwest monsoon seasonal rainfall over the Monsoon Core Zone (MCZ) consisting of most of the rainfed agriculture areas in the country is most likely to be above normal with more than 106% of LPA.

The southwest monsoon seasonal rainfall is most likely to be above normal over central India and south peninsular India (>106% of LPA), normal over northwest India (92-108% of LPA) and below normal over northeast India (<94% of LPA), according to the weather office.

While most parts of the country are expected to get above normal rainfall some states such as Jammu and Kashmir, Uttarakhand, north eastern states, some part of Odisha, southern part of west Bengal and some parts of Chhattisgarh are likely to get below normal rainfall.

The strong El Niño conditions observed over equatorial Pacific in the beginning of this year have weakened rapidly into weak El Niño conditions and currently transitioning towards ENSO neutral conditions, said Mohapatra, adding that the latest climate model forecasts indicate ENSO-neutral conditions are likely to get established during the beginning of the monsoon season and La Niña conditions are likely to develop during the later part of the monsoon season.

The El Nino conditions, which are known for deficient rainfall in India, are now at a moderate level and are expected to turn to La Nina by August-September with a probability of 69%, raising expectations of normal rainfall.

El Nino is the periodic warming of waters in the central Pacific Ocean, which led to an erratic monsoon in 2023, reducing India’s food grain production by 6.1% in the 2023-24 crop year (July-June). La Nina is its opposite and is favourable for the monsoon. ENSO or El Niño-Southern Oscillation relates to Pacific winds and sea surface temperatures.

The southwest monsoon provides about 70% of India's yearly rain and is vital for the agriculture sector that contributes 14% to the country’s GDP and supports over half of its 1.4 billion population.

Private forecaster Skymet said earlier this month that it expected a “normal” monsoon this year with rainfall expected to be 102% of the LPA.